Control device



E- J. DILLMAN CONTROL DEVICE Dec. 13, 1955 4 Sheets-Sheet 1 OriginalFiled May 11, 1948 INVENTOR. 1L. Da

M ATTORNEY E. J. DILLMAN CONTROL DEVICE Dec. 13, 1955 4 Sheets-She 2Original Filed May 11. 1948 IN VEN TOR.

Jag, ATTORNEY Dec. 13, 1955 E. J. DlLLMAN CONTROL DEVICE 4 Sheets-Sheet3 Original Filed May 11, 1948 PIC-3.8

. a R N m R w m T K A B 3 W11. 5 ||I|||| A. m X6 m a 5 H mm 0 W m 5am FE 7 III! 1 2 mil n 6 5 mm m 1955 E. .1. DILLMAN 2,727,106

CONTROL DEVICE Original Filed May 11, 1948 4 Sheets-Sheet 4 IN V EN TOR.

M ATTORNEY United States Patent CONTROL DEVICE Earnest J. "Dillman,"Detroit, Mich, .ass'ignor to Detroit (Iontrols Corporation, acorporation of Michigan Original application May 11, 19.48, Serial No.263%,

now Patent No. 2,638,121, dated May 12, 1953. Digisdsed and thisapplication May 6, .1953, Serial No.

8 Claims. (Cl. 200'--61.86)

This invention relates to new anduseful improvements in liquid fuelburner systems and more particularly to control devices therefor. 7

One of the objects of this invention is to provide a control systemhaving a plurality of liquid fuel burners having a common supply offuel.

Another object is to provide a control device for selectively directingthe flow of liquid fuel to each of a plurality of liquid fuel burners.

Another object is to provide a liquid flow controlling device having apressure determining means therein and having a means for leading fuelback to the source of supply at pressures below that determined by thepressure determining means.

Another object is to provide a control device having a means forselectively directing the flow of fuel to two burners and fortransferring control between two control systems which control theoperation of said burners.

Another object is to provide a novel valve and switch combination in aliquid fuel burner control device.

Another object is to provide a control device for a two burner controlsystem by which the fuel supply is discontinued to. one burner beforethe control valve.

novel means for inducing a snap or quick action of an operating member.

Other objects will-become apparent from time to time throughout thespecification and claims as hereinafter related.

This invention consists of the new and improved control system andcontrol device therefor and of the combination and cooperation of. theparts thereof which will be described more fully hereinafter and thenovelty of which will be particularly pointed out and distinctlyclaimed.

In the accompanyingdrawings to be taken as part of the specification,there is clearly and fully illustrated one preferred embodiment of thisinvention in which drawings:

Figure l is a view in front elevation of a control device embodying thisinvention,

Fig. 2 is a top plan view of this control device,

Fig. 3 is a sectional view taken on the section i-ine 3-3 of Fig. 2 ofthis control device and which shows the construction and relation of thecontrol valves to the various outlet passageways,

Fig. 4 is a sectional view taken onthe section line 44 of Fig. 2, andwhich shows the thermostatic means for operating this device,

Fig. 5 is a sectional view taken on the line 5-5 of Fig. 4 and whichshows the liquid inlet to the control device and the actuating levertherefor,

Fig. 6 is a sectional viewtaken on-the section line 66 of Fig. 5, c

Fig. 7 is a plan view. of this control device with the cover memberremoved and shown in partial section to show the means for adjusting thesnap acting device,

Fig. 8 is a bottom plan view of the cover member of this device whenremoved, and

Fig. 9 is a diagrammatic view of this control device installed in acontrol system for controlling a pair of liquid fuel burners.

Referring to the drawings by characters of reference, there is a controldevice 1 comprising a liquid fuel receiving casing 2 having an inletpassageway 3 and a pair of outlet passages 4, 5. The casing 2 has acover member 6 of an electric insulating material which is secured toand seals the open top of the casing, the cover member 6 being securedto the casing 2 on a flange 7 which we tends around the open top of thecasing. There is a valve casing member 8 which is secured to the covermember 6 along one end portion thereof. The valve casing 8 has a pair ofprojecting portions 9, it) which extend through a pair of apertures inthe cover member 6. The projecting portions 9, 10 are externallyscrewthreaded and are secured to the cover member 6 by a pair of nuts11, 12. The projecting portions 9, it have bores l3, 14 therein whichopen into smaller bores 15, 16 forming valve ports and cooperating withthe bores 13, 14 to form valve seats. There are a pair of valve members17, 13 which fit slidably in the bores 13, 14 and which function tocontrol flow of liquid fuel there through. The valve members 17, 18 areof polygonal cross-section to permit flow of fuel to the valve ports1'5, 16. The valve casing 8 has a pair of cylindrical cavities at eachend thereof in which are screv -threadedly secured a pair of plugmembers 19, 2d. The bores or ducts 1'5, 16 open respectively intopassages 21, 22; which communicate at one end thereof through bleedorifices 23, 24 into a bleed or auxiliary outlet passageway 25. Theother ends of the passages 21, 22 communicate with annular cavities 26,27 respectively which are closed by resilient elastic diaphragms 28, 29respectively of a pair of diaphragm type check valves. The plug members19, 2%) in the valve casing 8 are each hollow and have hollow operatingpistons 30, 31 therein which are held compressively against thediaphragms 28, 29 by helical springs 32, 33. The diaphragms 23, 2.9which are clamped in position by the plug members 1%, 2% respectively,re held compressively closing a pair of passages 34, 35 which open intothe outlet passages 4, 5. Secured to the under surface of the covermember 6 is a bracket 36 which supports the fulcrum pin 37 of anoperating lever 38 which controls the opening and closing movement ofthe valves 17, 18. The operating lever 33 fits at its opposite ends intolost-motion slots 39, id in the valves 17, 18. The operating lever 38 isadjustably secured to a lever supporting member 41 which is formed ofsheet metal having a plane central portion and downturned projections orears 42 at each end through which extends the pivot pin 37. There is asupporting member 43 of an electric insulating materiai which is securedto and carried by the lever supporting member 41. The operating lever 38has a grooved central portion which rides on the pivot pin 37 and has apair of apertures on opposite sides of the fulcrum pin 37' through whichextend a pair of bolts 44, 45 which are adjustably secured in thesupporting members il, 43. There is a helical spring 46 surrounding eachof the bolts 5 which is positioned between the lever supporting member41 and the lever 38 and which holds the lever 32"; compressively againsttheheads of the bolts 4%, 45. it is obvious then that the lever 38 canbe rotatably adjusted relative to the sup porting member i-l by properinward and outward adjustment of the bolts 44, 4-5, thereby permittingadjustment of the amount of opening of the control valves 17, 18.

The cover member 6 of the casing 2 carries four pairs of electricalcontact terminals or binding posts 47 which are connected to fixedcontacts 48 of an electric switch. There are four pairs of movableswitch contacts 49 which are carried by the supporting member 43 on thelever supporting member 41 and which are connected thereto by resilientarms 50. It is seen then that upon rocking movement of the lever in onedirection one of the valves is opened and one closed and two pairs ofmovable contacts are closed against their respective fixed contactswhile two pair of movable contacts are opened. The lever supportingmember 41 has a downturned and bifurcated projecting portion 51 at theend opposite the valves. There is a lever 52 which is pivoted on abracket 53 and which extends between the prongs of the bifurcatedprojection 51. The lever 52 when moved engages one or the other of theprongs of the bifurcated projection 51 and causes the lever and electriccontacts to be rocked. Positioned between flanges on the lever 52 thereis a pivoted member 54 which has a pair of annular shoulders cut intothe opposite faces thereof. The casing 2 has a pair of apertures 55, 56which are oppositely alined in line with the pivoted annular member 54.There is a plug member 57 which is screw-threadedly secured in theaperture 56 and which has an adjustment screw 58 extendinglongitudinally therethrough into the chamber enclosed by the casing 2.The adjustment screw 58 is enclosed by a cover member 59 which isscrew-threadedly secured to the exterior of the plug member 57. Theadjustment screw 58 has a small projecting portion 60 which projectsinto a cylindrical cavity in a spring supporting member 61. Thesupporting member 61 has an annular flange 62 thereon against whichbears one end of a helical spring 63, the other end of which bearsagainst one annular shoulder of the pivoted member 54. At the oppositeside of the casing 2 there is a plug member 64 which is screwthreadedlysecured in the aperture 55. The plug member 64 has a bore 65 extendingsubstantially along the longitudinal axis thereof, which bore is ofreduced size in the inner end portion thereof. There is a piston member66 which slidably fits the reduced end portion of the bore 65 and whichextends into the chamber enclosed by the casing 2 and which has anannular shoulder upon which seats a spring supporting member 67 having aflange 68. There is a helical spring 69 which is compressivelypositioned between the flange portion 68 of the member 67 and the otherannular shoulder of the pivoted member 54, the springs 69, 63 beingoppositely alined. Positioned in the enlarged portion of the bore 65 andextending partially into the reduced portion is an elastic plug member78 of a resiliently elastic material such as a rubber or syntheticrubber. The bore 65 at its enlarged end opens into a cylindrical recessor cavity 71 which is closed by a cover member 72. The enlarged open endof the bore 65 is closed off from the cavity 71 by a flexible diaphragm73 of a resiliently elastic material such as rubber or synthetic rubber.The diaphragm 73 is secured against the end wall of the recess 71 by thecover member 72 and abuts the plug member 78, the cover member 72 beingheld rigidly in position by an inturned annular flange 74. The covermember 72 has an aperture therein opening into the cavity 71 and inwhich is sealed a tube or conduit 75 which leads to a thermostatic bulbelement 76. The bulb element 76 contains an expansible fluid which isresponsive to temperature and operable to transmit an expansive force tothe cavity 71 which is expanded thereby and its force transmittedthrough the diaphragm 73 and plug 70 to move the piston 66. Theaforementioned movement of the piston 66 is transmitted through thespring 69 to the lever 52 for operating the control lever 38. The lever52 has a projecting portion 77 at its free end portion which extendsinto a cylindrical recess 78 in the bottom wall of the casing 2, thewalls of the cylindrical recess 78 functioning as limit stops for thelever 52. There is another lever 79 which is pivoted on a bracket 80 onthe side wall of the casing 2 and which has an adjustment screw or bolt81 at its free end portion. There is a threaded member 82screw-threadedly secured on the bolt 81 and to which is secured one endof a helical spring 83. The other end of the spring 83 is secured to ascrewthreaded member 84 on an adjustment bolt 85 which extends throughan aperture 86 in the end wall of the casing 2, the aperture 86 havingan enlarged outer end portion which is closed by a bolt-like closuremember 87. The lever 52 has an inturned flange portion 88 on its freeend against which is pivoted one end of a pivoted member 89, the otherend of which is pivoted against the mid-portion of the lever 79. Thepivoted member 89 is compressively held by the force of the spring 83between the lever 79 and the flange portion 88 of the lever 52 and isoperable to transmit a biasing thrust therebetween.

In operation this control device functions as follows:

Liquid fuel is supplied to the chamber enclosed by the casing 2 throughthe inlet 3 under pressure by a pump 98 (shown diagrammatically in Fig.9). This fuel is discharged through the open valve 14 under pressure andthrough the passages 16, 22 to the annular cavity 27 which is closed bythe diaphragm check valve 29. The check valve 29 is set to open at apredetermined pressure of say 60 p. s. i. at which pressure thediaphragm 29 forces the piston 31 into the cylindrical cavity in theplug member 20 against the spring 33. As the diaphragm 29 is moved, theopening to the passage 35 is opened to permit flow through that passageinto the outlet passage 5, which leads to one of the burners controlledby this device. When the heat output in the one burner has reached asufficient amount the thermostatic bulb 76 which is responsive to saidheat output will transmit fluid expansion to the chamber 71 and anexpansive force through the diaphragm and plug member as heretoforedescribed to the piston 66 which acts through the spring 69 to move thelever 52 against the force of the spring 63. The amount of forcerequired to move the lever 52 may be adjusted by the adjustment screw 58which determines the compressive force exerted by the spring 63 whichadjustment will determine the temperature of the bulb element 76 whichis required to cause the lever 52 to be moved. As the lever 52 is moved,the pivoted member 89 pivots therewith and causes the lever 79 to moveoutward thus tensioning the spring 83. When the lever 52 has moved to anover-center position the spring 83 acting through the lever 79 and thepivoted member 89 will cause the lever 52 to move through the remainderof its travel with a snap action. The movement of the lever 52 with asnap action will cause it to engage one of the prongs of the bifurcatedprojection 51 and to rock the lever 38 and electrical contact arms witha snap action. There is a friction spring 91 which is positioned betweenthe end portion 51 of the lever supporting structure 41 and thesupporting bracket 36 which functions to hold the lever supportingmember 41 in any predetermined position when a rocking force is notbeing applied thereto. This spring bears against two raised or embossedportions of the projecting portion 51 and will hold the lever supportingmember 41 at one of the two extremes of movement with the valve andswitch contacts closed while the lever 52 is moving the distance betweenthe prongs of the bifurcated projection 51. When the lever 52 engagesthe other prong of the bifurcated projection 51 the lever supportingmember 41 will begin to move and thus begin to open one of the valvesand one set of switch contacts and begin to close the other valve andthe other set of switch contacts. The lever 38 which operates the valves17, 18 extends into the slotted end portions 39, 40 of these valves andis operable to provide a lost motion in the opening of these valves.When the lever 38 begins its movement it must move from one side of oneof the slots 39 and 4G to the other side of the slot before the valvecan begin to open. The oil pressure at which the burner is operated isnor mally about 90 p; s. i. and this pressure is suflicicnt to resistopening of the valve which is closed until the operatingpressure dropsto a small valueof say/p. 8.1. The lost motion feature in the valves andthe pressure which holds the valve 17 closed is operable to hold thevalve closed while permitting the switch contacts .to open. With theswitch contacts open the pump is deenergized and when the pressure inthe valve casing drops to the lower pressure (10 p. s. i.) the valvesand switch contacts are permitted to move through the remainder of theirtravel to re-establish the pump and burner circuit and to open and closethe respective valves as required. The switch contacts which are openingand closed in sequential synchronization with the opening and closing ofthe valves are operable to switch between two sets of control circuitswhich control the operation of the pump 90 which supplies fuel to theopen one of the valves. The central outlet passageway 25 or bleedpassageway communicates through reduced openings or orifices 23, 24 withthe passages 21, 22 leading from the outlet 15, 16 from the valve 17,18. During periods when only one of the burners supplied by this controldevice is in operation the switching of the valve and switch contactswill deenergize the pump 911 but the inertia. of the pump will cause afuel pressure to continue for a short time and fuel could be suppliedthrough the open valve to the inactive burner. With the bleed outlet andlost motion valve opening described, this short supply of fuel throughthe inactive burner valve port would be so reduced in pressure as to beinsutlicient to open the check valve and would be bled through theorifices and discharged through the bleed outlet 25 and a connectingconduitbackto the source of fuel supply.

in 9 the control device heretofore described is shown in alled in acontrol system for controlling flow of fuel to a household heatingburner and a domestic water heating burner. in this systemthere is afuel sump 92 for supplying fuel to a conduit 93 leading tothe pump 99,the pump 91) supplying fuel through the conduit'94 to the inlet 3 of thecontrol device. From the control device 1 one conduit 95 leads to ahouse heating burner 96 and another conduit 97' leads to a domesticwater heating burner The burners 96, 98 are supplied with air by acommon motor driven fan 99 by which motor the pump 9% is driven. Thereis an air duct 100 leading from the fan 99 to the burner 96 and abranchduct 191 leading to the burner The stack 1612 from the burner 98 isconnected to the stack 1113 ofthehouse heating burner 96. Thethermostatic bulb element '76 is responsive'to the temperature of thewater supply and is inserted in the water heating jacket surrounding'theburner 93. The electric control system for the control of the burners96, 98 is as follows:

There is a main power source 1115 from which a pair'of conductors 1'96,1117 run to the terminals 103, 109 of an electric primary control device110. From the terminal 111 on the control device 110 a conductor 112runs to the terminal 113 of the motor of the fan '99 which is connectedto the main power source 105 by a conductor 11 1 leading from the otherfan motor terminal 115. The terminals 138, 1119 of the control device110 are connected to the primary 116 of a transformer 117. Thetransformer 117 has a secondary coil 118 which has three terminalconnections thereon. From one of the secondary terminals 119 a conductor120 runs to a thermostatic warp switch 121, the contacts 122, 123 ofwhich are normally closed. 'From the fixed contact 123 of the warpswitch 121 a conductor 124' leads to a terminal 125 or" the controldevice 110. From the terminal 126 of the transformer secondary 118 aconductor runs to a heater coil 127 for the thermal warp switch 121, theheater coil 127 being connected by a conductor 128 to a terminal 129 onthe control device 110. From the terminal 130 of the transformersecondary 118 a conductor 131'leads to a movable contact 132 of a bipolerelay switch 133. The fixed contact 134 of the relay switch 133 isconnected to the relay coil 135 which is in turn connected by conductor136 to the terminal 137 of the control device 110. The fixed relaycontact 134 is also connected by a conductor 138 to a terminal 139 ofthe control device'11tl and by'condoctors 14%, 141 and the closedcontacts 142, 143 of a thermostatic stack switch 144- to the controldevice terminal 145. There is a jumper 146 which leads from thetransformer primary 116 to a second movable contact 147 coopera'ole witha fixed contact 14f; of the relay switch 11.9. The fixed contact 1.48 ofthe relay switch 133 is connected by a conductor 149 to the terminal111. On the control device 1 there are a plurality of pairs of fixedswitch contacts 150 and 151, 152 and 153, 154 and 155, 156 and 157 withwhich cooperate the movable pairs of contacts 49. There is a conductor158 running from the terminal 125 of the control device to the fixedcontact 152 of the control device 1. The terminal 137 of the controldevice 110 is connected by a conductor to the contact 153, which contactis connected by a conductor 16% to the terminal 161 of a room thermostat162. The thermostat terminal 161 is connected to a bimetal element 163which carries a movable contact 164 and is also connected to acompensating heater coil 165 which is in turn connected by a conductor166 to the contact 155 of the control device 1. The fixed contact 167which cooperates with the movable contact 164 is connected by acondoctor 168 to the contact 157 of the control device 1. There is ajumper wire 169 connecting the contacts 152 and 156 of the controldevice 1 and a similar jumper 17d connecting the contacts 151, 155. Fromthe contact 151 a conductor 171 leads to the terminal 129 of the controldevice 1111 and a conductor 172 similarly connects the contact 154 tothe terminal 145. From the terminal a conductor 173 leads to the fixedcontact 174 of a thermostatic stack switch 175, the other contact ofwhich (176) is normally closed thereagainst. From the movable contact176 of the thermostatic stack switch 175 a conductor 177 leads to theterminal 139 of the control device 11tl.

In operation this control system functions as follows:

The control device 1 is shown diagrammatically and corresponds to theposition shown in the various views of the device itself. In theposition shown, the hot water tank 1514 has cooled and the movable pairsof contacts 49 have closed against the fixed pairs of contacts 151) and151, 152 and 153 to complete a control circuit for supplying fuel to thehot water heater. In this position (see Fig. 3) the valve 18 of thecontrol device is open and operable to permit passage of fuel to the hotwater heater 9% through conduit 97. A circuit is completed from the mainpower source 105 to conductors 106, 1th? to the primary 116 of thetransformer 117. With the transformer 117 energized a circuit iscompleted from the transformer secondary terminal 119 by way ofconductor 1211, closed contacts 122, 123 of the warp switch 121 andconductor 12 1 to the control device terminal 125. From the terminal thecircuit runs through conductor 153 to the contact 152 of the controldevice 1, through the closed switch contacts to the contact 153 andthence by conductor 159 to the terminal 137 of the control device 110.From the terminal 137 the circuit runs by conductor 136 to the coil ofthe relay and thence by conductor 138 to the terminal 139. From theterminal 139 the circuit runs by conductor 177 through the closedcontacts 174, 176 of the stack switch 175 and by conductor 173 tocontact 159 of the control device 1. From contact the circuit iscompleted through the closed contacts 49 to contact 151 and thence byconductor 171 to terminal 129 of the control device 110. From theterminal 129 the circuit is completed by conductor 128 and the heatercoil 127 to the terminal 126 on the transformer secondary 118. It isthus seen that a circuit is completed through the coil of the relayswitch 133 to the closed contacts of the timer warp switch 121 andthrough the closed contacts of the stack switch 175. When the relayswitch 133 is energized the movable contacts 132, 147 are closed againstthe fixed contacts 134, 148. When the contacts 147, 148 are closed thecircuit is completed from the main power source by conductor 196 andconductor 146, the closed contacts 147, 148 and conductor 149 to theterminal 111 of the control device 110. From the control terminal 111the circuit runs by conductor 112 to the motor of the fan 99 and byconductor 114 back to the main power source. It is then seen that uponenergization of the relay switch 133 the circuit is completed throughthe fan motor for operation of the fan 99 and for operation of the pump91) which supplies fuel through the open valve 18 and outlet in thecontrol device 1 to the hot water burner 93 through the conduit 97.Simultaneous with the establishment of the circuit for energization ofthe fan and pump a circuit is completed through the closed contacts 132,134 of the relay switch from the terminal 130 of the transformersecondary 118. This circuit is a holding circuit which runs from theterminal 118 by conductor 131, closed contacts 132, 134, the relay coil135, conductor 136 to the terminal 137 of the control device 110. Fromthe terminal 137 the circuit runs by conductor 159, contacts 152, 153,conductor S, terminal 125, conductor 124, the closed contacts 123, 122of the warp switch 121 and conductor 120 back to the terminal 119 of thetransformer secondary 118. Since the initial energizing circuit for therelay switch 133 was established through the heater 127 for the warpswitch 121 and the stack switch 175, it will be obvious that unless theinitial circuit is opened within a short predetermined time the heater127 will cause the contacts 122, 123 of the warp switch 121 to open thusdeenergizing the relay 133 and stopping the fan and pump. The stackswitch 175 has a thermostatic element positioned in the stack from thehot water burner and upon occurrence of flame in the hot water burnerthe thermostatic element will cause the contact 176 to move away fromthe contact 174 in the stack switch 175 thus breaking the circuitthrough the heater coil 127 of the warp switch 121 and deenergizing theinitial circuit for energizing the relay 133. The burner 98 will thencontinue to heat until the domestic hot water supply is heated to thedesired temperature at which time the thermostatic power element bulb 76will have been heated sufficiently to transmit power to the controldevice 1 and cause the levers to move thus closing the valve 13 andopening the valve 17 and opening and closing the corresponding switchcontacts. As was described heretofore the lost motion in the opening ofthe valve 17 is such that the circuit through the switch contacts acrossthe terminals 150 and 151, 152 and 153 in the control device 1 arebroken and the pump 90 de-energized prior to the opening of the valve 17so that fuel will not be ejected through the valve 17 should thehousehold burner 96 not require heat. With the valve 17 open and theswitch contacts 154 and 155, 156 and 157 closed which occurssequentially to the opening of contacts 150 and 151, 152 and 153 thecontrol device 1 is now in position to supply fuel to the householdburner 96 as required. As described before, the transformer 117 of thecontrol device 119 is energized at all times from the main power sourceWith the switch contacts moved as described in the control device 1 anew circuit will now be completed from the terminal 119 of thetransformer secondary 118 through the contacts 122, 123 of the warpswitch 121 and by terminal 125 and conductor 153 to the contact 152 ofthe control device 1. From the contact 152 the circuit runs by thejumper 169 to and through the closed contacts 156, 157 and by conductor168 to the fixed contact 167 of the room thermostat 162. If the roomthermostat 162 is demanding heat and the contact 164 is closed againstthe contact 167 the circuit will be completed through the bimetal 163and terminal 161, by conductor 160 to contact 153 of the controldevice 1. From the'contact 153 conductors 159, 136 run to the coil ofthe relay switch 133. From the relay coil 153 a circuit runs byconductor to the closed contacts 142, 14-3 of the household burner stackswitch 144 and by conductors 141, 172 to the contact 154 of the controldevice 1. From the contact 154 the circuit runs through contact 155, theconductor 166 to the compensating heater on the room thermostat 162. Abranch circuit runs from a contact 155 by jumper 170 to contact 151which is connected by conductor 171 to a terminal 129 on the controldevice 110. The circuit is then completed from the terminal 129 byconductor 128 and the warp switch heater 127 to the terminal 126 on thetransformer secondary 118. From this circuit it is seen that the circuitis completed through the room thermostat 162 as heat is called for andthrough the closed contacts of the stack switch 144, the relay coil 135,and through the contacts of the warp switch heater 121. When the relayswitch 133 is energized and the contacts 147 and 148 closed, the circuitis completed as previously described through the fan motor forenergizing the fan 99 and the pump 90 for supplying of fuel to thehousehold burner through the open valve 17 and outlet 4 by conduit 95.Upon closing of the contacts 132, 134 of the relay switch 133, a circuitis established from the transformer secondary terminal 130 through theclosed contacts 132, 134, the relay coil 135, conductors 136, 159, 160to the room thermostat 162. From the room thermostat 162 the circuitruns by conductors 168, contacts 156, 157, jumper 169, conductors 153,124, the closed contacts 122, 123 of the warp switch 121 and conductor120 leading back to the transformer secondary terminal 119. As wasdescribed before, the initial circuit for the energization of the relaycoil 135 runs through the closed contacts of both the stack switch 144and the warp switch 121, and the warp switch heater 127. Since theholding circuit for the relay coil 135 through the closed contacts 132,134 also runs through the closed contacts of the warp switch 121 it isnecessary that the initial relay coil energizing circuit be brokenwithin a short predetermined time or the opening of the warp switchcontacts 122, 123 will de-energize both the initial and the holdingcircuits of the relay 133 and will stop the fan and pump. As wasdescribed for the control system of the water heater, the stack switch144 performs a similar function to the stack switch 175 in that it isresponsive to the occurrence of flame in the household burner 96. Uponoccurrence of flame in the household burner 96 the stack switch contacts142, 143 will open thus deenergizing the circuit through the warp switchheater 127 and leaving the holding circuit to the relay coil 135 incontrol of the operation of the fan and pump. As was describedheretofore the holding circuit for the relay coil 135 includes theswitch contacts of the control device 1 and the contacts 164, 167 of thethermostat 162 so that if the room thermostat should be satisfied therelay coil will be deenergized or if the household water supply shouldcool a sufiicient amount that the switches of the control device 1 aremoved the household heating circuit would similarly be broken. It shouldbe noted that the check valves 28, 29 and the bleed outlet 25 asdescribed heretofore permit the bleeding of fuel back to the sump 92 bya conduit 93*. This bleed arrangement together with the delayed openingof the valve as previously described prevents fuel from being dischargedinto the household burner 96 when the control device 1 switches overfrom the water heating burner 98 if the room thermosat 162 is notcalling for heat and causes fuel pressure created by the inertia of thepump 96 to be relieved through the bleed outlet 25 back to the sump 92.

From the description heretoforegiven it is seen that there is provided apair of circuit networksffor controlling a two burner system whereby thedemand of heat by the domestic water heating system will switch thecontrol device 1 to a position for supplying fuel to the water heatingburner 9.8 and switch .to a control system for the burner 98. Similarly,when .the water supply is adequately heated the control device willswitch fuel back to the house heating burner 96 and ,place its controlsystem in control.

This application is a division of my co-pending application, Serial No.26,429, filed May 1-1, -1948,'forControl Device.

Having thus described the invention, what is claimed and is desired tobe secured by Letters Patent of the United States is:

l. A control devicecomprising a' cas'ing having afluid inlet and a pairof fluid outlets, a pair of valves for controlling fluid flow throughsaid outlets, a rockable lever operatively connected to said valves andoperable upon rocking movement to open one of said valves andto closethe other of said valves, a pair of electric switch contacts carried bysaid lever, said contacts being adapted for controlling electriccircuits for controlling supply of fluid to said casing, one of saidcontacts being closed upon rocking movement of said lever, said closedcontact being operable to control flow of fluid to said casing fordischarge through the open one of said valves, means to move said leverand lost motion means on said valves cooperable with said lever andoperable to permit said lever on movement to open said closed contactsbefore opening the closed valve.

2. A control device comprising a casing having a fluid inlet and a pairof fluid outlets, a pair of valves for controlling fluid flow throughsaid outlets, a rockable lever operatively connected to said valves andoperable upon rocking movement to open one of said valves and to closethe other of said valves, a pair of electric switch contacts carried bysaid lever, said contacts being adapted for controlling electriccircuits for controlling supply of fluid to said casing, one of saidcontacts being closed upon rocking movement of said lever, said closedcontact being operable to control flow of fluid to said casing fordischarge through the open one of said valves, means operable uponpredetermined movement to move said lever with a snap action, and meansto hold said lever at its limit of movement until said operating meanshas moved the predetermined distance necessary for snap movement therebyto prevent opening of the closed contact and the closed valve until saidoperating means is in position to close the other contact and the othervalve with a snap action.

3. A control device comprising a casing having an inlet and having anopen top, a cover member of an electrical insulating material closingand sealing said top, a fixed electric switch contact carried by saidcover member, a valve casing carried by said cover member and having anoutlet member extending through said cover member into said controldevice casing, a valve in said outlet member for controlling flow offluid from said control device casing, a rockable lever fulcrumed on andcarried by said cover member, a switch contact arm carried by said leverand having a movable contact cooperable with said fixed contact, saidlever being cooperable with said valve and operable to open and to closethe same, and means carried by said control device casing for actuatingsaid lever.

4. A control device comprising a casing having a fluid inlet and a pairof fluid outlets, a pair of valves for controlling discharge of fluidfrom said outlets, an operating lever operable upon movement to open oneof said valves and to close the other of said valves, a pair of fixedswitch contacts, a pair of movable switch contacts carried by resilientarms on said lever, said lever being operable upon movement to close oneof saidmovable vcontacts againstone ofsaid fixed contacts and to open.the other contacts, lost motion means on said valves cooperable withsaid lever and operable to permit said lever on movement to open theclosed pair of contacts before opening the closed valve, operating meansfor moving saidlever, a pair of limit stops for determining .the rangeof movement of said operating means and said lever, and said valves andsaid contacts being arranged to close before said operating meansreaches the limit stops so that the operating means must travel beyondthe distance necessary to close the valves and the contacts therebyflexing the resilient contact carrying arms and the lever so that thecontacts and the valves will be held compressively in closed position.

5. A control device comprising a casing having a fluid inlet and a pairof fluid outlets, a pair of valves lfor controlling fluid flow throughsaid outlets, a rockablelever operatively connected to said valves andoperable upon rocking movement to open one of said valves and to closethe other of said valves, a pair of electric switch contacts carried bysaid lever, said contacts being adapted for controlling electriccircuits for controlling supply of fluid to said casing, one of saidcontacts being closed upon rocking movement of said lever, said closedcontact being operable to control flow of fluid to said casing fordischarge through the open one of said valves, operating means operableto move said lever with a snap action, a pair of limit stops fordetermining the range of movement of said operating means and means tohold said lever against one of said limit stops until said operatingmeans has moved the predetermined distance necessary for snap movementthereby to prevent opening of the closed contact and the closed valveuntil said operating means is in position to close the other contact andthe other valve with a snap action.

6. A control device comprising a casing having a fluid inlet and a pairof fluid outlets, a pair of valves for controlling fluid flow throughsaid outlets, a rockable lever operatively connected to said valves andoperable upon rocking movement to open one of said valves and to closethe other of said valves, a pair of electric switch contacts carried bysaid lever, said contacts being adapted for controlling electriccircuits for controlling supply of fluid to said casing, one of saidcontacts being closed upon rocking movement of said lever, said closedcontact being operable to control flow of fluid to said casing fordischarge through the open one of said valves, means operable uponpredetermined movement to move said lever with a snap action, and aspring positioned between said lever and said casing, said spring beingoperable to hold said lever at its limit of movement until saidoperating means has moved the predetermined distance necessary for snapmovement thereby to prevent opening of the closed contact and the closedvalve until said operating means is in position to close the othercontact and the other valve with a snap action.

7. A control device comprising a casing having a fluid inlet and a pairof fluid outlets, a pair of valves for controlling fluid flow throughsaid outlets, a rockable lever operatively connected to said valves andoperable upon rocking movement to open one of said valves and to closethe other of said valves, a pair of electric switch contacts carried bysaid lever, said contacts being adapted for controlling electriccircuits for controlling supply of fluid to said casing, one of saidcontacts being closed upon rocking movement of said lever, said closedcontact being operable to control flow of fluid to said casing fordischarge through the open one of said valves, means operable uponpredetermined movement to move said lever with a snap action, means tohold said lever at its limit of movement until said operating means hasmoved the predetermined distance necessary for snap movement thereby toprevent opening of the closed contact and the closed valve until saidoperating means is in position.

11 to close the other contact and the other valve with a snap action,and lost motion means between said lever and said operating meansoperable to permit movement of said operating means a predetermineddistance Without movement of said lever.

8. A control device comprising a casing having a fluid inlet and a pairof fluid outlets, a pair of valves for controlling fluid flow throughsaid outlets, a rockable lever operatively connected to said valves andoperable upon rocking movement to open one of said valves and to closethe other of said valves, a pair of electric switch contacts carried bysaid lever, said contacts being adapted for controlling electriccircuits for controlling supply of fluid to said casing, one of saidcontacts being closed upon rocking movement of said lever, said closedcontact being operable to control flow of fluid to said casing fordischarge through the open one of said valves, operating means operableto move said lever, snap acting means cooperable with said operatingmeans, lost motion means on said valves cooperable with said lever andoperable to permit said lever on movement to open the closed pair ofcontacts before opening the closed valve, and friction means operable tomaintain said contacts and valve members in a predetermined positionuntil said operating means has moved a predetermined distance necessaryfor snap movement thereby limiting opening movement of the closedcontact and the closed valve until said operating means is in positionto close the other contact and the other valve with a snap action.

References Cited in the file of this patent UNITED STATES PATENTS nn-m a

